package tongwentongshu.com.app.utils;

import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Rect;
import android.net.Uri;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;

/**
 * @author xujun  on 2016/11/27.
 * @email gdutxiaoxu@163.com
 */

public class ImageZip {
    /**
     * 压缩图片的方法
     */
    public static void zipImage(String savePath) {
        BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeFile(savePath, options);
        options.inSampleSize = computeInitialSampleSize(options, 480, 480 * 960);
        options.inJustDecodeBounds = false;
        Bitmap bitmap = BitmapFactory.decodeFile(savePath, options);
        File file = new File(savePath);

        try {
            if (!file.exists()) {
                file.createNewFile();
            }
            FileOutputStream fos = new FileOutputStream(savePath);
            bitmap.compress(Bitmap.CompressFormat.JPEG, 90, fos);
            fos.flush();
            fos.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
        bitmap.recycle();
        bitmap = null;
    }

    public static Bitmap getZipImage(String savePath) {
        BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeFile(savePath, options);

        options.inSampleSize = computeInitialSampleSize(options, 480, 480 * 960);
        options.inJustDecodeBounds = false;
        Bitmap bitmap = BitmapFactory.decodeFile(savePath, options);
        bitmap.recycle();
        bitmap = null;
        System.gc();
        return bitmap;
    }

    public int computeSampleSize(BitmapFactory.Options options, int minSideLength, int maxNumOfPixels) {
        int initialSize = computeInitialSampleSize(options, minSideLength,
                maxNumOfPixels);
        int roundedSize;
        if (initialSize <= 8) {
            roundedSize = 1;
            while (roundedSize < initialSize) {
                roundedSize <<= 1;
            }
        } else {
            roundedSize = (initialSize + 7) / 8 * 8;
        }
        return roundedSize;
    }

    public static int computeInitialSampleSize(BitmapFactory.Options options, int minSideLength,
                                               int maxNumOfPixels) {
        double w = options.outWidth;
        double h = options.outHeight;
        int lowerBound = (maxNumOfPixels == -1) ? 1 : (int) Math.ceil(Math
                .sqrt(w * h / maxNumOfPixels));
        int upperBound = (minSideLength == -1) ? 128 : (int) Math.min(
                Math.floor(w / minSideLength), Math.floor(h / minSideLength));
        if (upperBound < lowerBound) {
            // return the larger one when there is no overlapping zone.
            return lowerBound;
        }
        if ((maxNumOfPixels == -1) && (minSideLength == -1)) {
            return 1;
        } else if (minSideLength == -1) {
            return lowerBound;
        } else {
            return upperBound;
        }
    }

    /**
     * @param options   参数
     * @param reqWidth  目标的宽度
     * @param reqHeight 目标的高度
     * @return
     * @description 计算图片的压缩比率
     */
    private static int calculateInSampleSize(BitmapFactory.Options options,
                                             int reqWidth, int reqHeight) {
        // 源图片的高度和宽度
        final int height = options.outHeight;
        final int width = options.outWidth;
        int inSampleSize = 1;
        if (height > reqHeight || width > reqWidth) {
            final int halfHeight = height / 2;
            final int halfWidth = width / 2;
            // Calculate the largest inSampleSize value that is a power of 2 and keeps both
            // height and width larger than the requested height and width.
            while ((halfHeight / inSampleSize) > reqHeight && (halfWidth / inSampleSize) > reqWidth) {
                inSampleSize *= 2;
            }
        }
        return inSampleSize;
    }

    /**
     * @param src
     * @param dstWidth
     * @param dstHeight
     * @return
     * @description 通过传入的bitmap，进行压缩，得到符合标准的bitmap
     */
    private static Bitmap createScaleBitmap(Bitmap src, int dstWidth,
                                            int dstHeight, int inSampleSize) {
        // 如果是放大图片，filter决定是否平滑，如果是缩小图片，filter无影响，我们这里是缩小图片，所以直接设置为false
        Bitmap dst = Bitmap.createScaledBitmap(src, dstWidth, dstHeight, false);
        if (src != dst) { // 如果没有缩放，那么不回收
            src.recycle(); // 释放Bitmap的native像素数组
        }
        return dst;
    }

    /**
     * @param res
     * @param resId
     * @param reqWidth
     * @param reqHeight
     * @return
     * @description 从Resources中加载图片
     */
    public static Bitmap decodeSampledBitmapFromResource(Resources res, int resId,
                                                         int reqWidth, int reqHeight) {
        final BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true; // 设置成了true,不占用内存，只获取bitmap宽高
        BitmapFactory.decodeResource(res, resId, options); // 读取图片长宽，目的是得到图片的宽高
        options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight); // 调用上面定义的方法计算inSampleSize值
        // 使用获取到的inSampleSize值再次解析图片
        options.inJustDecodeBounds = false;
        Bitmap src = BitmapFactory.decodeResource(res, resId, options); // 载入一个稍大的缩略图
        return createScaleBitmap(src, reqWidth, reqHeight, options.inSampleSize); // 通过得到的bitmap，进一步得到目标大小的缩略图
    }

    /**
     * @param pathName
     * @param reqWidth
     * @param reqHeight
     * @return
     * @description 从SD卡上加载图片
     */
    public static Bitmap decodeSampledBitmapFromFile(String pathName, int reqWidth, int reqHeight) {
        final BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeFile(pathName, options);
        options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
        options.inJustDecodeBounds = false;
        Bitmap src = BitmapFactory.decodeFile(pathName, options);
//        return createScaleBitmap(src, reqWidth, reqHeight, options.inSampleSize);
        return src;
    }


    public static Bitmap decodeSampledBitmapFromUri(Context context, Uri uri, int reqWidth, int reqHeight) {
        InputStream is = null;
        try {
            is = context.getContentResolver().openInputStream(uri);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }

        final BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeStream(is, new Rect(), options);
        options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
        options.inJustDecodeBounds = false;
        Bitmap src = BitmapFactory.decodeStream(is, new Rect(), options);

        return src;
    }

    public static void saveBitmap(String path, Bitmap mBitmap) {
        File f = new File(path);
        FileOutputStream fOut = null;
        try {
            if (!f.exists()) {
                f.createNewFile();
            }

            fOut = new FileOutputStream(f);
        } catch (IOException e) {
            e.printStackTrace();
        }
        mBitmap.compress(Bitmap.CompressFormat.PNG, 100, fOut);
        try {
            fOut.flush();
            fOut.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }


}